MongoDB v7 new features support in PMM

Thanks for the feedback. I was reviewing old roadmap items from the incubator and found this one. I’d need to have a closer look at this.

to get this and “Mongo8 features in PMM” done - just a list of metrics is not enough, as PMM team has no knowledge about “why this is important to the users???“
So mainly and to take a look to get a more clear picture of “what’s and why “.

Hi , task has status incomplete and if got it right we didn’t get good information what exactly needs to be included to PMM. Do you know what should be done? We still collect all these metrics, but we don’t use a big portion of them. We’ve made some Mongo related dashboards last year, but I’m not sure if they are related to new Mongo 7 features or not.

or → where we are with this ? (see Kimberly’s comment below). Are we missing a lot of metrics that were added in MongoDb 7?

I will place some info here below now.   
I have posted some info in the mongodb slack channel over the last several days - will put that same info in a Notion doc and link here as well later.

However, it is not really new features that I was alerting about.
There are parameter name changes, new parameters, new statistics, and changing metric names along with new metrics. 

==> Those will likely impact PMM and the exporter.

The biggest changes  relate to new metrics around indexBuilds and new statistics relating to Chunk Migrations and Sharding.
There is a also change to the output of serverStatus.

The links below go to more details.

1. new parameter indexBuildMinAvailableDiskSpaceMB -  which stops index builds if disk space is too low.

2. New metrics for indexBuilds: 

• indexBuilds.killedDueToInsufficientDiskSpace

• indexBuilds.failedDueToDataCorruption

3. New Sharding Statistics for Chunk Migrations

Available starting in MongoDB 7.1 (and 7.0, 6.3.2, 6.0.6, and 5.0.18).

MongoDB includes the following new sharding statistics for chunk migrations:

• shardingStatistics.countDonorMoveChunkCommitted

• shardingStatistics.countDonorMoveChunkAborted

• shardingStatistics.totalDonorMoveChunkTimeMillis

• shardingStatistics.countBytesClonedOnRecipient

• shardingStatistics.countDocsClonedOnCatchUpOnRecipient

• shardingStatistics.countBytesClonedOnCatchUpOnRecipient

plus LOTS MORE overall ... 

Then Compatibility Changes to Capped Collections and deprecated commands getAuditConfig and setAuditConfig  - use auditConfig cluster parameter now 
auditConfig

Renamed serverStatus Metric:
Starting in MongoDB 7.1, the serverStatus metric countDocsClonedOnDonor is now shardingStatistics.countDocsDeletedByRangeDeleter
More details can be found here:
https://www.mongodb.com/docs/upcoming/release-notes/7.1/

MORE changes to Database Commands. mongosh shell Methods <mainly around Atlas search indexes,

==> NEW Fields in the currentOp command and its db.currentOp()meth  and associated aggregation metrics 

• currentOp.admissionPriority

• currentOp.collUuid

• currentOp.startTime

• currentOp.samplesPerSecond

• currentOp.sampledReadsCount

• currentOp.sampledWritesCount

• currentOp.sampledReadsBytes

• currentOp.sampledWritesBytes

•  

  • $currentOp.collUuid

•  

  • $currentOp.startTime

•  

  • $currentOp.samplesPerSecond

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  • $currentOp.sampledReadsCount

•  

  • $currentOp.sampledWritesCount

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  • $currentOp.sampledReadsBytes

•  

  • $currentOp.sampledWritesBytes

queryAnalyzer Metrics

•  

  •  

    • queryAnalyzers.activeCollections

•  

  •  

    • queryAnalyzers.totalCollections

•  

  •  

    • queryAnalyzers.totalSampledReadsCount

•  

  •  

    • queryAnalyzers.totalSampledWritesCount

•  

  •  

    • queryAnalyzers.totalSampledReadsBytes

•  

  •  

    • queryAnalyzers.totalSampledWritesBytes

That info is from the v7.0 Release Notes:
https://www.mongodb.com/docs/upcoming/release-notes/7.0/

•  

  • All of the above will likely need to be looked at more closely.

Yay .   

===>>> JAN W